The conventional story about Russia has been one of power reclaimed after the fall to chaos during the 1990s. Oil, gas and autocracy have restored it to the ranks of world powers. Some of the more hyperbolic commentary has gone so far to say that, along with China, Moscow has created an entirely new model to challenge western liberalism.

Yet what most strikes me about Russia is its isolation. For all its resurgent hydrocarbon revenues and its considerable, albeit residual, military power, Moscow is essentially friendless. As for a superior system of capitalism, when was the last time you heard an international politician of any consequence hold up Russia as their chosen paradigm?

Moscow can claim the odd loyal acolyte, sure. Many of the former Soviet republics among its neighbours judge it wise to stay on side with the present regime. Last year’s Russian invasion of Georgia served, in Voltaire’s famous phrase, “pour encourager les autres”. Beyond the post-Soviet space, mavericks such as Venezuela’s Hugo Chávez see some advantage in travelling in Moscow’s slipstream.

But look for eager and willing allies – governments and peoples that feel an instinctive affinity with today’s Russia or who see in its society something to borrow for themselves – and, well, Moscow is out there on its own. To put it another way, what country in the world wants to be more like Russia? I cannot think of a shorter list.

I was reminded of this isolation the other day when Vladimir Putin stepped out for what has become a familiar August ritual. The Russian prime minister, stripped to the waist and bestride a horse, posed for the camera in a studied show of summer machismo. Russians were reassured that they have a strong man at the helm; the world was reminded it had better not mess with Mr Putin.

That was the theory anyway. To my mind, these vainglorious photo-shoots are more a measure of weakness. Sad really – a middle-aged man desperate to show the world he still has his physique. The Russian prime minister would do better to buy himself a sports car. More seriously, Mr Putin’s apparent compulsion to flaunt his torso offers an unfortunate metaphor for Russia itself: a great, but waning power deluding itself that a show of muscle is the way to cling on to past glory.

Why a delusion? After all, US power, you could say, is based on its unparalleled economic and military might. For a time George W. Bush thought that nothing else mattered. In the wake of September 11 2001, the US decided that friends and foes alike could be bullied into line.

Yet even the world’s sole superpower learned pretty quickly the limitations of a foreign policy based on instilling fear. Supreme military might was not enough. Mr Bush realised too late that power needs legitimacy. Anti-Americanism emerged as a rival superpower.

Barack Obama’s administration seems to have understood the importance of what the political scientists call “normative” power. States are strong when others want to imitate them. For some that means an admiration for US democratic values, for others enthusiasm for America’s cultural and economic vibrancy.

Travel to Beijing and you will hear high-ranking Chinese policymakers speak in awe of the US higher education system and of its economy’s capacity for technological innovation. Much as Mr Putin would like to pretend otherwise, Russia scarcely merits even a passing mention in such conversations. Beijing considers it has little, if anything, to learn from Moscow.

China sees its neighbour as a declining power. Temporarily re-energised, of course, by a surge in oil and gas revenues and by Mr Putin’s nationalism; but for all that a state that is squandering its petro-bounty and one in which almost every medium-to-long term indicator points in the direction of decay.

Joe Biden hit the mark a few weeks ago with a candid assessment of Russia’s prospects: a falling population, a withering economy and severe psychological hangover from the loss of empire. The US vice-president got into some trouble for his undiplomatic choice of words, but his assessment is pretty much the consensus outside Russia. For all that Mr Putin, with the help of oil revenues, has revived the country’s spirit, Russia is indeed shrinking fast. By some estimates its present population of 140m or so will be closer to 100m by the middle of the present century.

It is not just the ravages of low birth and high mortality rates. The Kremlin’s crony capitalism has done precious little to modernise the nation’s economy or to rebuild a crumbling infrastructure.

Faced with the progressive hollowing out of Russian power, Mr Putin’s response is a foreign policy in which the organising emotions are grievance and belligerence. The west is held responsible for the chaos of the 1990s. Moscow will now deploy coercion – cutting off the gas or more direct intervention in former Soviet republics such as Georgia and Ukraine – to restore hegemony over its own neighbourhood.

Coercion can work for a while. A hopelessly divided Europe needs the gas. The US administration wants Russia’s help in dealing with a range of global issues. Moscow has cards to play on nuclear arms reduction, Iran and international terrorism, as well as its huge reserves of hydrocarbons.

In spite of the long-term prognosis, this embrace of victimhood makes Russia hard to deal with now. So far Mr Obama seems to have got it about right: engage respectfully with Moscow where there are mutual interests or useful trade-offs, humour Mr Putin’s vanity, but forget grandiose ideas about “strategic partnerships”.

Moscow will discover eventually the limitations of its capacity to obstruct. It is starving itself of foreign technology and investment. Making life difficult for the west is not the same as shaping a different international landscape. Even those who now pay notional fealty to Moscow are hedging their bets with China or the west.

Mr Putin may not care. Perhaps the braggadocio that drives him to pull on military fatigues and take off his shirt for the camera tells him also that all is well as long as the world shows Russia respect. In that case, Russian power will wither as surely as will Mr Putin’s physique. To quote the plain-speaking Mr Biden, it is hard when you lose an empire, but you cannot cling on to the past indefinitely.